Low grade brain tumors of childhood have not received nearly as much attention from late effects researchers as have higher grade/malignant brain tumors, yet they constitute a sizable portion of pediatric brain tumor survivors. The little scientific data available indicates that these patients are at increased risk for sub-optimal outcomes, and that their neurobehavioral late effects profile differs from that found in higher grade brain tumors. This gap in our understanding hampers efforts to address the neurobehavioral liabilities particular to this class of pediatric brain tumor. The objective of this study is to address this major gap in our knowledge by investigating the neuropsychological vulnerabilities and indices of Socioeconomic Status (SES) in adulthood related to childhood low grade brain tumors and their treatment. A landmark epidemiologic study, the Childhood Cancer Survivor Study (CCSS), will be used to identify a sample of 260 patients, now ranging in age from mid-20s to mid-50s, treated for childhood low grade brain tumors as well as controls matched for age, gender, and education of family of origin. An aggressive recruitment/data collection strategy will evaluate participants through 14 testing sites located throughout the country with a battery of neuropsychological tests sensitive to the effects of brain tumors in diverse locations (Specific Aim A). Specific Aim B will investigate disease- and subject-related predictors of outcome. This study improves upon existing research in several respects: (a) It uses an ongoing, highly successful epidemiologic study (CCSS) to identify a large, diverse sample of adults treated as children for low grade brain tumors, (b) A neurobehavioral assessment plan is proposed grounded in previous research that promises to elucidate the neuropsychological vulnerabilities in this population in unprecedented detail, (c) Increased methodological rigor will be achieved through a carefully matched control group, and (d) A remote follow-up design will permit the assessment of adult sequelae of childhood brain tumors, as well as an exploration of how early vulnerabilities might interact with the aging process. The true legacy of childhood cancer spans the entire life, and so the importance of understanding the life trajectories of survivors cannot be over-estimated. A better understanding of the degree and nature of the chronic/remote effects in these patients is critical to the identification for early intervention those at risk, as well as to promote the development of less toxic treatments.